'07 Tahoe mods?

[harshman]

So here is the deal. I have an '07 Tahoe with the AFM (displacement on demand) 5.4 engine. In theory it runs on 4 cylinders at cruising. However, it rarely will drop down to 4 unless I coast. The only thing different I have on the Tahoe is 20” wheels with a 285 tire – bigger footprint and a bit more drag than stock. What I am wondering is if I buy a cold air and exhaust (slightly more HP) will this help it get into the 4 cylinder mode more often? Do any of you guys have one or know of someone that does?

The HP gains that the aftermarket boasts about are debatable and until I see some dyno figures I'll continue to be a skeptic. I'm not looking to be the fastest Tahoe in my area. But if I can gain significantly more MPG average with a few mods, I'll do it.

[slownova]

i put a magnaflow cat back on one while back. it also has 22s on it. i wouldn't say it went into afm more, but it had no problem getting into it. i didn't have much seat time before so i can't give a honest comparo. you could deffinatly tell the diffrence when it did it with the cat back though.

[harshman]

cool. i was looking at gibson exhaust (quiet) and k and n air filter. you would think that there would be some tech on this one.

[68sixspeed]

I'm not sold on the k&n cold air kits- I pulled one off my 2000 pickup with a 5.3; all it did was made noise- no hp gain. I called them on it- they basically said it "might" give 6hp after the computer learns it. I didn't bother with one for my '05 silverado.

I wonder if someone with tuning softare for the engine computer could change the cyl shutdown point? I had an 07 burban for a rental and noticed the same thing, 4cyl mode only when coasting- but it was 30 below and we had 8 guys in it, so I wasn't sure if the cold affected it.

[Rick Dorion]

Exhaust always helps. I would change out the filter on the stock air intake and not spend the $ on K&N, etc.

[MarkM66]

Isn't it a 5.3?

I think a CIA and exhaust may help at with power WOT, but even a stock set-up, if restrictive, should allow pleanty of air in and out of the engine at low rpm cruising down the highway, like you're after.

Does it have mechanical fan? An electric may free up a little power, at cruise.

[XCESSIV]

Use the GM exhaust and ram air its warranty for 36 month they are nice pieces

[Skip Fix]

I think this is the correct address www.performancetrucks.net (http://www.performancetrucks.net). They have alot of good info there.

[zbugger]

Cold air intake doesn't usually do much when doing around town driving. On the highway, and getting on the highway, might be different. If I was to choose one, it'd be made by Volant. It didn't really add any noise and it did make a noticeable difference in power. This was on a 2500 Dodge Ram pickup truck with the Hemi. The exhaust will help you more with gas mileage.

[Nine Ball]

I think this is the correct address www.performancetrucks.net (http://www.performancetrucks.net). They have alot of good info there.

Definitely the best late model GM truck performance site! :cheers: